Two organizations in the United States (Residential Energy Network, or RESNET and Building Performance Institute, or BPI) have developed nationally recognized systems to evaluate energy usage in homes. Certification in either program involves being tested on a thorough knowledge of sound building practices, an advanced understanding of energy science, health and safety issues in a home and how to analyze a home’s energy usage. An extremely high level of proficiency, both theoretical and practical, is expected.
The Home Energy Rating System (HERS) is a nationally recognized certification that has been developed to assist Americans to make informed choices about the energy-efficiency of prospective homes.
A detailed analysis of the home’s design, materials and solar orientation is entered into a computer program, along with many other details of energy use, air infiltration levels and heating and cooling equipment. Air infiltration blower-door testing is performed as part of a HERS test.
A house is awarded ratings that show its energy-efficiency performance and how it compares to other homes. The HERS rater can also offer expert recommendations on the best way to improve and reduce energy costs.
The Building Performance Institute is a nationally recognized developer of standards for the Home Performance industry. BPI certifies individuals and accredits contractors that meet their exacting standards. BPI certification is based upon a broad Building Science curriculum. BPI certified analysts have a solid scientific foundation of knowledge upon which to accurately assess exisiting buildings. They have been trained to understand building issues relating to energy efficiency, building durability, and human health. BPI energy performance analysis involves blower door testing, combustion appliance testing and analysis of the whole structure. See the Home Performance Contracting page.